Mechanical counter limiting device



Aug. 23, 1955 L. c. STANLEY 2,715,998

MECHANICAL COUNTER LIMITING DEVICE Filed Oct. 24, 1951 IZ 24 26* 11 1019 zo I N V EN TOR. l Ano/v7 JTAAQ [Y Arian/vir MECHANICAL COUNTER LIMITING DEVICE LamontpC. Stanley, Cedar Rapids, Iowa, assignor to Collins Radio Company, Cedar Rapids, Iowa, a corporation of Iowa Application (lctober 24, 1951, Serial No. 252,845

6 Claims. (Cl. 23S-1.17)

This invention relates in general to counting mechanisms and in particular to a gear counter stop which locks the counting wheels so that they will operate only between predetermined limits.

It is oftentimes desirable to operate a counting mechanism which is limited so that it moves only between predetermined limits instead of being continuously movable. For example, if it is desired to indicate angular positions from to 360 degrees, it is advantageous to eliminate all numbers above 360.

It is an object of this invention, therefore, to provide a counter wheel stop which limits the rotation of the counter wheels.

Another object of this invention is to provide an improved counter that may be adjusted so that it only moves between defined limits.

Yet another object of this invention is found in the provision for a gear counter stop that locks transfer pinions to limit their travel.

Further advantages, objects and features of this invention will become apparent from the following description and claims when read in View of the drawings in which:

Figure l is a bottom view of a counter mechanism with the apparatus of this invention installed therein;

Figure 2 is a sectional View taken on line 2 2 of Figure l; and

Figure 3 is a perspective View of the gear counter stop and the counter drum transfer pinions.

Figure l illustrates a three wheel counter mechanism with counter wheels 1t), 11, and 12 rotatably supported on the shaft 13. The counter wheels each have the numerals 0 9 printed about their peripheries. Between the counter wheels and 11 is a suitable transfer motion which moves wheel 11 one-tenth of a turn each time counter wheel 10 rotates a full turn. Likewise, a suitable transfer motion is mounted between counter wheel 11 and counter wheel 12 and moves wheel 12 one-tenth of a turn each time that wheel 11 makes one revolution.

The wheel 1t) designates the units digit, the wheel 11 designates the tens digit, and the wheel 12 designates the hundreds digit.

The transfer motion between the wheels 10 and 11 comprise pinion 14 which is supported by shaft 16. The pinion 14, as best shown in Figure 3, has alternate teeth 15 which extend the full transverse dimension and intermediate teeth which extend only half way across the transverse dimension. The pinion 14 engages a gear 18 which is rigidly attached to the counter wheel 11.

A gear is connected to wheel 10 and engages a driving gear 17 which may be turned manually or by a suitable driving means.

A counter wheel 10 has attached to it adjacent the gear 18 a disc 19 which rides between a pair of teeth on the pinion 14. It is to be noted that only alternate teeth 15 engage disc 19. A slot 21 is formed in the disc 19 so that when slot 21 is aligned with one of the locking teeth nited States Patent O Crt 2,715,998 Patented Aug. 23, 1955 ICC 15, the pinion 14 rotates and turns wheel 11 one-tenth of a turn.

A second pinion 22 is supported on a shaft 23. The pinion 22 intermittently drives counter wheel 12 through a gear 24 attached thereto. A disc 26 is attached to wheel 11 adjacent the gear 24. A slot 27 is formed in the disc 26. The counting mechanism described is conventional and well known to those skilled in the art. For a more detailed description, reference may be made to the patent to Bliss, Number 2,483,359.

The locking gear stop of this invention comprises a mutilated gear 28 which has teeth formed on two portions so that diiferent portions are alternately engaging the transfer pinions 14 and 22. The rst portion 29 engages the pinion 14. A transverse projection 31 is attached to gear 28 and binds pinion 14 when they engage.

The other portion of the gear designated as 32, engages the pinion 22 at times when the pinion 14 does not engage the portion 29. The pinion 22 also locks against the member 31 at the upper end position. The projection 31 is so spaced that the pinion 14 locks against it at the Zero position and the pinion 22 locks against it at the 360 degree position. The portion 32 engages pinion 22 from Zero to 300 degrees and the pinion 14 engages the portion 29 from 300 to 360 degrees.

It is to be noted that when the pinion 22 engages the portion 32 the gear 28 turns only one-tenth as fast as when the pinion 14 engages it. This is because shaft 16 rotates ten times as fast as shaft 23. lt is to be understood, of course, that the limits of 360 degrees have been used merely for illustrative purposes and any other limits may be used.

Although this invention has been described with respect to a particular embodiment thereof, it is not to be so limited as changes and modications may be made therein which are within the full intended scope of the invention as deiined by the appended claims.

l. Means for limiting the angular motion of a counting mechanism comprising, a mutilated gear which has teeth formed on two portions, a iirst transfer pinion of the counting mechanism engageable with a rst portion of said mutilated gear, a second transfer pinion of the counting mechanism engageable with the second portion of the mutilated gear, and a transverse projection extending across the mutilated gear to bind the rst and second transfer pinions at the lower and upper limits of rotation.

2. Means for limiting the angular motion of a counting mechanism having counter wheels rotatably supported with discs and gears and pinions between each wheel cornprising, a mutilated gear formed with a rst toothed portion which extends partially around the gear, a second toothed portion extending the rest of the way around the mutilated gear and laterally offset from the rst portion, a first pinion of the counting mechanism engageable with a rst gear and disc between a pair of the counting wheels and the first toothed portion, a second pinion of the counting mechanism engageable with the second toothed portion, and a transverse projection extending across the mutilated gear at the junction of the iirst and second toothed portions.

3. A locking means for a counter mechanism having counter wheels and transfer motions between each of the counting wheels comprising, a mutilated gear which is formed with two toothed portions with the rst toothed portion offset laterally and radially from the second toothed portion, a transverse projection extending across said mutilated gear at the junction of the rst and second toothed portions, a first pinion of the counting mechanism which forms a portion of the transfer motion engageable with the rst toothed portion of the mutilated gear, and a second pinion which forms a portion of the transfer toothed portion for the remainder of the circumference of r the mutilated gear, a transverse projection extending across the mutilated gear at the junction p'oint between the first and second toothed portions, a rst pinion of a transfer motion engageable with the tirst toothed portion, and a second pinion of a second transfer motion engageable with the second toothed portion.

5. Means for limiting the angular motion of a counting mechanism between upper and lower limits comprising, a mutilated gear rotatably supported adjacent the counting mechanism and formed with two toothed portions laterally oftset from each other, a transverse projection formed on the mutilated gear at the junction of the toothed portions, a rst pinion of the counting mechanism engageable with the rst toothed portion, a second pinion 4. engageable with the second toothed portion, and one side of said transverse projection engageable with said first pinion to provide a lower counter limit and the other side of said transverse projection engageable with said second pinion to provide an upper counter limit.

6. Means for limiting the angular motion of a counting mechanism comprising, a mutilated gear, a plurality of teeth portions on said gear, each of said teeth portions laterally offset from each other and encompassing a different angular portion of said gear from the remaining gear portions, a plurality of transfer pinions of said counting mechanism with each transfer pinion engageable with a dilerent toothed portion, and a transverse projection formed across said mutilated gear to bind said transfer pinions at the lower and upper limits of rotation.

References Cited in the file of this patent UNlTED STATES PATENTS 1,192,193 Hart July 25, 1916 2,463,594 Brigham Mar. 8, 1949 FOREIGN PATENTS 267,285 Great Britain Mar. 17, 1927 

